[jQuery] Make 'this' child 'ul' appear

[Alex]

Hey guys,

I have a menu like this:

<li><a href="#">Test</a>
  <ul>
    <li><a href="#">Another</a></li>
    <li><a href="#">Another</a></li>
    <li><a href="#">Another</a></li>
  </ul>
</li>
<li><a href="#">Test</a>
  <ul>
    <li><a href="#">Another</a></li>
    <li><a href="#">Another</a></li>
    <li><a href="#">Another</a></li>
  </ul>
</li>

I want to be able to hover over a <li> and have its corresponding
child 'ul' show.

I have tried this jQuery but it won't work, any ideas why?

$(document).ready(function(){
  $("li").hover(function(event){
    $("this > ul").show();
  });
});

I'm guessing it's my interpretation of the 'this' selector but I need
a hand...

Thanks,
Alex